Two-lever shift mechanism for an internal-linkage transfer case

Abstract

An apparatus and method for converting an internal-linkage type of a transfer case from single lever to dual lever control includes a sleeve that is adapted for placement into a housing of the transfer case. A pivot pin is disposed in the sleeve and defines a pivot axis. The pivot pin passes through a first pivot hole in a first arm and a second pivot hole in a second arm. The first arm includes a first arcuate end at one end thereof and the second arm includes a second arcuate end at one end thereof. The first and second arcuate ends are each adapted to cooperate with a member in the transfer case sufficient for the first arm to select either a two or a four wheel drive mode and for the second arm to select either a high or a low gear range when the first and second arms are pivoted about the axis. A first and a second shift lever are attached to the first and second arms and a protective boot covers at least a portion of the housing.

What is claimed is: What is claimed is:  
     
       1. A two-lever shift mechanism for use with an internal-linkage type of a transfer case, comprising: 
       (a) a sleeve that is adapted to fit into a housing of said transfer case; said housing including a pair of pivot pin bore holes disposed through opposite walls thereof;  
       (b) a first arm extending through said sleeve and including a first arcuate end at a bottom end thereof that is adapted to engage with a first member in said transfer case when said sleeve is disposed in said housing and select between a two and a four wheel drive mode, said first arm including a first arm pivot hole;  
       (c) a second arm extending through said sleeve and including a second arcuate end at a bottom end thereof that is adapted to engage with a second member in said transfer case when said sleeve is disposed in said housing and select between a high and a low gear range mode, said second arm including a second arm pivot hole; and  
       (d) a pivot pin, each end thereof disposed in one of said pivot pin bore holes and wherein said pivot pin defines a pivot axis and wherein said pivot pin passes through said first arm pivot hole of said first arm and said second arm pivot hole of said second arm thereby securing said first arm and said second arm in said sleeve adjacent with respect to each other whereby said first arm and said second arm are adapted to pivot about said axis in said sleeve.  
     
     
       2. The two-lever shift mechanism of  claim 1  wherein said first arm includes means for attaching a first shift lever thereto at an end opposite to said first arcuate end. 
     
     
       3. The lever shift mechanism of  claim 1  wherein said second arm includes means for attaching a second shift lever thereto at an end opposite to said second arcuate end. 
     
     
       4. The two-lever shift mechanism of  claim 1  wherein said sleeve includes means for securing said sleeve in said housing. 
     
     
       5. The two-lever shift mechanism of  claim 1  including a boot disposed over at least a portion of said housing and said sleeve and said first and second arms. 
     
     
       6. The two-lever shift mechanism of  claim 5  wherein said boot includes a pair of openings adapted to permit said first arm and said second arm to extend therefrom. 
     
     
       7. The two-lever shift mechanism of  claim 5  wherein said boot is made of an elastomeric material. 
     
     
       8. The two-lever shift mechanism of  claim 1  including a first shift lever, said first shift lever adapted for attachment to said first arm. 
     
     
       9. The two-lever shift mechanism of  claim 1  including a second shift lever, said second shift lever adapted for attachment to said second arm. 
     
     
       10. A method for converting an internal-linkage type of a transfer case from a single shift lever control into a dual shift lever control, comprising: 
       providing a sleeve to fit into a housing of said transfer case and providing a pivot pin in said sleeve to define a pivot axis;  
       providing a first arm with a first pivot hole disposed over said pivot pin and adapted to pivot about said axis, said first arm including means for engaging with a first member of said transfer case sufficient to select either a two or a four wheel drive mode; and  
       providing second arm with a second pivot hole disposed over said pivot pin and proximate to said first arm and adapted to pivot about said axis, said second arm including means for engaging with a second member of said transfer case sufficient to elect either a high or low gear range.  
     
     
       11. The method of  claim 10  including the step of placing a protective boot over at least a portion of said housing. 
     
     
       12. The method of  claim 10  including the step of boring out a portion of an interior of said housing sufficient to permit placing said sleeve therein.